The rest of the Library carries a footer that declares the Library articles are copyleft. That is, you can copy articles only when you give appropriate credit. There has now been a court case to enforce this:

A federal appeals court has overruled a lower court ruling that, if sustained, would have severely hampered the enforceability of free software licenses. The lower court had found that redistributing software in violation of the terms of a free software license could constitute a breach of contract, but was not copyright infringement. The difference matters because copyright law affords much stronger remedies against infringement than does contract law. If allowed to stand, the decision could have neutered popular copyleft licenses such as the GPL and Creative Commons licenses. The district court decision was overturned on Wednesday by the United States Court of Appeals for the Federal Circuit.

The copyright holder in the case is Robert Jacobsen, the lead developer of the Java Model Railroad Interface, a software package used by model railroad enthusiasts. A firm called Kamind Associates downloaded parts of Jacobsen's project, stripped out the copyright notice and other identifying information, and began redistributing the modified version without Jacobsen's approval.

You should read the rest of the article especially if you have your own web site.